Sql statement execution flow in oracle

As promise in Oracle 9i Architecture post here is new post for how SQL statement processe internaly. This is for them those whi are planning to start career as Oracle DBA. If they want to make clear picture of Oracle Architecture then first of all they need to understand how sql statement procees in oracle.These are [...]

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Tuning PGA memory in Oracle10g

Checking PGA for each sessions You can check session level PGA using V$SESSTAT and V$SESSION view and also you can check the username, who is using that memory. SELECT s.value,s.sid,a.username FROM V$SESSTAT S, V$STATNAME N, V$SESSION A WHERE n.STATISTIC# = s.STATISTIC# and name = ‘session pga memory’ AND s.sid=a.sid ORDER BY s.value; VALUE SID USERNAME [...]

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Wait Statistics in Oracle 10g

When a SQL is submitted by a user to Oracle database, it never happens that Oracle will execute the SQL continuously at one go. Oracle process never get to work on the execution of statement without any interruptions. Often the process has to pause or wait for some event or some other resource to be [...]

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